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G Wadell

Publications and source records attributed to G Wadell.

At least 145 records · Page 8Linked to original sources
PubMed1981

Molecular epidemiology of adenoviruses: alternating appearance of two different genome types of adenovirus 7 during epidemic outbreaks in Europe from 1958 to 1980.

Four genome types of adenovirus serotype 7 (Ad7, Ad7a, Ad7b, and Ad7c) were identified by use of DNA restriction enzymes BamHI, EcoRI, and SmaI. We obtained information on the distribution of the four Ad7 genome types by typing 68 Ad7 isolates obtained in the Netherlands from 1958 to 1979 and 36 Ad7 isolates obtained in Sweden from 1964 to 1980. The Ad7 prototype was never detected, and only seven isolates were genome-typed Ad7a. Ad7b and Ad7c accounted for 94% of the genome-typed isolates obtained from patients. Ad7c was isolated in the Netherlands during 1958 to 1969, but only Ad7b has been detected there since 1970. In Sweden, Ad7c was recovered between 1964 to 1972, but only Ad7b has been isolated there since 1973. In conclusion, the newly recognized Ad7b and Ad7c genome types, which in the Netherlands and Sweden represent virtually all genome-typed isolates from patients, show a mutually exclusive appearance.

Adenoviridae Infections↗
PubMed1980

New human adenovirus (candidate adenovirus 36), a novel member of subgroup D.

A new adenovirus (candidate Ad36) was isolated from the feces of a girl with enteritis. It has been biological and biophysical properties of an adenovirus, with a particle diameter of 750 +/- 10 A in thin sections and with a fiber length of 190 A. The virus belongs to subgroup D. It is distinct both in neutralization and hemagglutination-inhibition from all other human adenoviruses; it also shows a unique DNA restriction pattern.

Adenoviruses, Human↗
PubMed1980

Epidemic outbreaks of adenovirus 7 with special reference to the pathogenicity of adenovirus genome type 7b.

Adenovirus type 7 (Ad 7) is the serotype among the 36 recognized adenovirus types which most frequently has been associated with severe illness. Three different epidemic patterns of Ad 7 infection can be distinguished: 1) the first appears during the winter among infants with median age below two years, has characteristic symptoms of high fever and pneumonia and an outcome that may be fatal: 2) the second appears in the fall among children with median age seven years, has characteristic symptoms of high fever, pneumonia, abdominal symptoms and meningism and an outcome that is favorable; 3) and the third has been seen as acute respiratory disease among military recruits. In the United States, the last mentioned outbreaks require prophylaxis in the form of a live enteric-coated vaccine. DNA restriction site mapping demonstrated the occurrence of three distinct viral entities of Ad 7, which have been designated Ad 7 prototype, Ad 7a (the vaccine strain) and the Ad 7b genome type. In the present study, 36 isolates obtained from outbreaks with the first and the second epidemic patterns were analyzed by restriction endonucleases Bam HI and Sma I. All were identified as the newly recognized Ad 7b genome type. It is concluded that this genome type is responsible for a large portion of the severe infections caused by Ad 7. The epidemic nature of Ad 7 and the severe illness noted among infants indicate that vaccination of institutionalized infants could be considered during years when Ad 7 epidemics appear.

Adenoviridae Infections↗
PubMed1980

Restriction endonucleases in identification of a genome type of adenovirus 19 associated with keratoconjunctivitis.

Adenovirus type 19 (Ad19) was first associated with disease in 1973 when several outbreaks of keratoconjunctivitis were reported from Europe and North America. We have examined Ad19 isolates by deoxyribonucleic acid restriction with BamHI, BglI, and SmaI restriction endonucleases. All keratoconjunctivitis-associated Ad19 isolates were identical but different from the Ad19 prototype. The total number of resolved restriction fragments of the Ad19 prototype genome was 31, only 17 of which migrated as the restriction fragments of keratoconjunctivitis-associated genomes. We conclude that two different genome types of Ad19 exist, one of which has been responsible for the recent outbreaks of keratoconjunctivitis.

Adenoviruses, Human↗
PubMed1980

Direct identification of enteric adenovirus, a candidate new serotype, associated with infantile gastroenteritis.

Two enzyme-linked immunosorbent assay techniques for detection of adenovirus in stools were developed. The first, which is group-specific, detects the 35 established adenovirus types and, in addition, enteric adenoviruses associated with infantile gastroenteritis. The second technique, which is type-specific, selectively detects enteric adenovirus. The efficiency of these techniques was assayed on nine coded stool specimens from Glasgow children. Eight of nine was classified as adenovirus by the group-speicific enzyme-linked immunosorbent assay. The six enteric adenovirus specimens were antigenically distinct from each of the 35 established adenovirus types but not from each other. They are suggested to represent a new adenovirus serotype which appear to be associated with gastroenteritis without clear-cut respiratory symptoms.

Adenoviruses, Human↗
PubMed1980

An outbreak of respiratory disease due to a type 5 adenovirus identified as genome type 5a.

A cluster of adenovirus type 5-caused acute respiratory diseases was observed in Prague in the autumn-winter season of 1978/79. An analysis of viral DNA by sequence-specific restriction enzymes in two out of 39 isolates revealed that these isolates, identical to each other, were clearly distinct from adenovirus type 5 prototype strain. The designation "adenovirus genome type 5a" is suggested for these isolates.

Adenoviridae Infections↗
PubMed1979

Identification of an enteric adenovirus by immunoelectroosmophoresis (IEOP) technique.

Infantile gastroenteritis can be caused by several of the established adenovirus types. There are also adenoviruses that defy in vitro cultivation but have been recognized by electron microscopy. One isolate of these viruses, which have been designated enteric adenoviruses, has been characterized. Several of the established adenovirus types are shed in stools over long periods. The conditions for direct identification of enteric adenoviruses by immunoelectroosmophoresis (IEOP) have therefore been evaluated. Application of this technique requires highly specific reagents. However, a high prevalence of antibodies in rabbits reacting with human rotavirus was noted. For these reasons, immunoadsorbent purified antibodies were prepared. Because of the difficulty in purifying immunogens from stools, an immunization procedure characterized by immunization with adenovirus subunits bound to affinity chromatography beads was elaborated. An identification procedure for adenoviruses causing infantile gastroenteritis based a) on IEOP using group-specific and monospecific antibodies and b) on the determination of the in vitro cultivatability is suggested.

Adenoviridae Infections↗
PubMed1979

Preparation of specific antisera against adenoviruses by affinity bead immunization (ABI).

Certain adenovirus types can be replicated only to low titer in tissue cultures. Other, such as adenovirus strains associated with infantile gastroenteritis, cannot be replicated in vitro. A method which allows preparation of specific antisera has therefore been evaluated. The procedure involves coupling of group-specific antibodies against adenovirus capsid subunits to CNBr-activated Sepharose 4B; reaction of crude virus suspensions with immobilized adenovirus-specific IgG; elimination of contaminating material by extensive washing using a wide pH range; and immunization with adenovirus immunogens immobilized on the beads. Efficient immunization was obtained with immunogen doses of both 50 ng and 50 microgram. The immunization procedure which has been designated affinity bead immunization (ABI) could therefore have a wide applicability in cases where the relevant immunogen constitutes a minor fraction of a crude preparation.

Adenoviruses, Human↗
PubMed1979

Classification of human adenoviruses by SDS-polyacrylamide gel electrophoresis of structural polypeptides.

The virion polypeptide compositions of 15 human adenovirus types, representing all members of subgroups B and C and selected members of subgroups A and D, have been analyzed by SDS-PAGE. The capsid polypeptides II, III, IIIa and IV displayed a pattern of apparent molecular weights which was characteristic for each adenovirus serotype analyzed. Adenovirus serotypes belonging to the same subgroup were also demonstrated to share an apparent molecular weight pattern of the internal structural polypeptides in the following manner: Subgroup A:V-resolved into two bands of 46--48.5 K and 51--51.5 K; VI-25.5 K; and VII-18 K. Subgroup B:V-53.5--54.5 K; VI-24 K; and VII-18 K. Subgroup C:V-48.5 K; VI-24 K; and VII-18.5 K. Subgroup D:V-50.5 K; VI-23.5 K; and VII-18 K. Adenovirus type 4: V-48 K; VI-24.5 K; and VII-18 K. The structural polypeptides represent a major portion of the adenovirus gene products. It is therefore proposed that the apparent molecular weight differences of viral polypeptides be used (i) to confirm the identification of an adenovirus type, and (ii) for subgroup classification of adenoviruses and, consequently, that adenovirus type 4 should be classified as a member of a separate subgroup designated E.

Adenoviruses, Human↗
PubMed1978

Preparation of sera for typing of adenovirus infections by immunofluorescence.

The conditions for preparation of adenovirus antisera with group, subgroup and type-specific reactivity to be used in the immunofluorescence technique have been evaluated. Group-specific antibodies were prepared by passing an antiserum against virions or hexons of one serotype through an immunosorbent column containing soluble viral components of an adenovirus type belonging to a different subgroup. The group-specific antibodies were recovered from the solid phase by elution at pH 2.8. Reagents specific for subgroup I and II were obtained by passing anti-dodecon sera through an immunosorbent column containing soluble viral components from heterologous subgroups. In this case antibodies not attaching to the absorbent were recovered. Sera against fibers of subgroup III members could be used as subgroupspecific sera without absorption. Type-specific antibodies were prepared by removal of antibodies of other specificities by passing anti-virion or anti-hexon sera through immunosorbent columns containing soluble viral components of an adenovirus type belonging to the same subgroup. Reagents specific for seven adenovirus types representing Rosen's three subgroups were prepared according to the outlined procedures.

Adenoviridae Infections↗
PubMed1978

Demonstration of three different subtypes of adenovirus type 7 by DNA restriction site mapping.

Restriction site mapping of the genomes of eight different isolates of adenovirus serotype 7 (Ad7) has been performed with six different restriction endonucleases. In this analysis, 37 different restriction sites were localized. Three distinctly different cleavage patterns of the genomes of the Ad7 strains were observed. These strains could not be distinguished by serological techniques. The following three subtypes were defined on the basis of their restriction site patterns: the Ad7 prototype, represented by strain Gomen originally isolated from a case of pharyngitis; subtype Ad7a, represented by the Ad7 vaccine strain and strains isolated from undifferentiated respiratory disease and from a healthy carrier; and a third subtype of Ad7, represented by three strains which were isolated from Swedish patients, all having pronounced clinical symptoms indicating severe systemic infection. A comparison of the restriction site maps of the protype of Ad3 and the three subtypes of Ad7 indicated greater differences in the position of restriction sites between strains of Ad7 than between strains of the two serotypes. This technique is consequently recommended to obtain a more precise definition of distinct entities of viruses.

Adenovirus Infections, Human↗
PubMed1977

Structural polypeptides of adenovirus type 16 incomplete particles.

The polypeptides of adenovirus type 16 incomplete particles, with average buoyant densities of CsCl of 1.33, 1.318, 1.305, and 1.299 g/cm3 and DNA content of less than 1 U genome size, were compared with the polypeptides of the complete virion (density, 1.344 g/cm3, and 22 x 10(6) daltons of DNA) and late polypeptides in infected cells by using sodium dodecyl sulfate-gel electrophoresis. In agreement with other serotypes studied (types 2 and 3), the light particles lack polypeptides V, VI, and VII. In adenovirus type 16, eight other major polypeptides are found, with apparent molecular weights of 59,000 (59K), 46K, 31K, 30K, 28K, 27K, 26K, and 19K. The 30K to 31K and 27K to 28K polypeptides are phosphorylated. The 27K and 19K polypeptides are precursors, whereas the 31K, 30K, and 26K polypeptides are chase products in the cell, as are polypeptides VI, VII, and VIII. The 26K polypeptide is proposed to be an intermediate in processing since it disappears from the young virions upon chasing. Although chase products, the 31K and 30K polypeptides are only associated with particles having buoyant density lower than 1.318 g/cm3. Polypeptides V and VII are only present in particles containing more than one quarter of the genome. No trace of cell histones could be detected in the purified incomplete particles. A major constituent of the incomplete particles, the 46K polypeptide, was rapidly labeled in the cell, and loss of radioactivity from this band was detectable only after 7 to 18 h of chase.

Adenoviruses, Human↗